In last week’s article, we looked at general equivalency mappings and how they may or may not be used in medical coding, data analyses and their effect on medical billing software. Click on this link for the ANSWERS to last week’s Challenge Questions on GEMS!

Coding Conventions for ICD-10-CM

In the ICD-10 CM Official Guidelines, the abbreviations, punctuation, symbols, and other conventions used in the Tabular List (code numbers and titles), can be found in Section IA under “Conventions Used in the Tabular List.” These include inclusion/exclusion terms, Not otherwise specified (in the patient records) (NOS) or Not elsewhere classified (in the ICD-10 code book) (NEC), dagger, asterisk and other coding conventions. Sound Familiar!

In ICD-10 CM, similarly to ICD-9 CM, within code book chapters, blocks and three- and four- character codes there are usually listed a number of other diagnostic terms in addition to the code title. These are known as inclusion terms and are given as examples of diagnostic statements or terms to be classified to that chapter, block or rubric. Exclusion terms are also three- and four-character codes and contain lists of conditions preceded by the word ‘Excludes’. These conditions are to be coded elsewhere, not within the chapter, or code range.

The Dagger and the Asterisk

Specific to ICD-10-CM, you need to become familiar with the use of the symbols known as the dagger (†) and the asterisk (*) next to certain codes. Use of this so-called dual coding system allows the creation of combinations of codes through attachment of daggers and asterisks to describe a condition in terms of its underlying cause or etiology (†) and its current manifestation (*). This enables a better description of the medical care provided and resources used in treatment.

“And”, Point Dash .-

Finally, two more coding conventions you will see in the Tabular List are the “and” in code titles and the point dash .- When you see the symbol known as point dash .- used as a replacement for the fourth character of a subcategory, it means that a fourth character exists and you should look it up in the appropriate category in the Tabular List to complete the code. (In ICD-9 CM, you would see a “check for 4th or 5th digit), which meant that you need additional digits to complete the code.) In the example above the dash in the fourth position means that the D58 category has been subdivided and you have to determine, by using the information in your diagnosis, which of the subcategories is appropriate. See presentation for more on ICD-10-CM Coding Conventions.